1.Christy Matthewson

Notable Facts: Christy Matthewson was one of the best pitchers to ever play. In 1918 he enlisted in the army and joined the Chemical Corps. In France he came into contact with toxic gas. As a result he developed tuberculosis and eventually died.

Baseball Seasons Lost: After his baseball career.

2.Ted Williams

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Branch Of Military: Marines

Year Enlisted: 1942

Conflict: World War II and Korean War

Notable Facts: Enlisted immediately following his first triple crown season. Served as a flight instructor during World War II. Was recalled in 1952 for Korea where he flew combat missions.

4.Hoyt Wilhelm

Notable Facts: Wilhelm was a staff sergeant in charge of a heavy gun unit in World War II (including at The Battle of The Bulge. In 1945 while in Germany his unit was under heavy attack when shrapnel tore into his hand and back. He left the service with a Purple Heart.

Baseball Seasons Lost: Three minor league seasons.

5.Joe DiMaggio

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Branch Of Military: Army

Year Enlisted: 1942

Conflict: World War II

Notable Facts: Was an Army physical education instructor. Was a sergeant when he left the military to return to baseball.

Baseball Seasons Lost: 3

6.Warren Spahn

Branch Of Military: Army

Year Enlisted: 1942

Conflict: World War II

Notable Facts: Spahn enlisted after the 1942 season, while he was still in the minors. He fought all over Europe including at the Battle of the Bulge. While in Remagen, Germany, Spahn was responsible for helping maintain traffic across the last active bridge across the Rhine. During an attack on their position shrapnel tore up his foot. Spahn received a Bronze Star, Purple Heart, and a battlefield commission as a second lieutenant.

Baseball Seasons Lost: Three minor league seasons.

7.Yogi Berra

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Branch Of Military: Navy

Year Enlisted: 1944

Conflict: World War II

Notable Facts: Berra volunteered as soon as he came of age. He was a gunner's mate on D-Day at Normandy. He also served in North Africa and played baseball throughout his time in the Navy.

Baseball Seasons Lost: Before his baseball career.

8.Hank Greenberg

Notable Facts: Hank Greenberg was dead set on serving during World War II. He was initially deemed unfit for service due to having flat feet. He was later cleared for duty, but when he was honorably discharged at the age of 28, he re-enlisted with the Army Air Forces.

9.Jackie Robinson

Notable Facts: A second-lieutenant, Robinson was court-martialed for refusing to move to the back of an Army bus. He was eventually cleared of any and all wrong-doing.

Baseball Seasons Lost: Before his baseball career.

10.Pee Wee Reese

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Branch Of Military: Navy

Year Enlisted: 1943

Conflict: World War II

Notable Facts: Reese served three years in the Pacific theater. Where he spent most of his time in Guam.

Baseball Seasons Lost: Three.

11.Whitey Ford

Branch Of Military: Army

Year Enlisted: 1951

Conflict: Korean War

Notable Facts: Whitey Ford was a dominant rookie in 1950, but after his first season he enlisted in the Army for the Korean War.

Baseball Seasons Lost: Two.

12.Dizzy Dean

(St. Louis Post-Dispatch)

Branch Of Military: Army

Year Enlisted: 1926

Conflict: N/A

Notable Facts: When Dizzy Dean was 16 he convinced an Army recruiter that he was 18 so that he could enlist. He was stationed in Texas for three years where his reputation for being "dim" began.

Baseball Seasons Lost: Before his baseball career.

13.Roger Staubach

(News/ZUMA Press/Icon SMI)

Branch Of Military: Navy

Year Service Began: 1964

Conflict: Vietnam

Notable Facts: Staubach attended the Naval Academy, so when he graduated, he had to fulfill his required service before he could play pro football. This included a tour in Vietnam. He was finally able to join the Dallas Cowboys in 1969, five years after being drafted.